From the IT live blog: "She is wearing an orchid brooch on her coat, a gift from Mappin Webb and Waterford for the 60th anniversary of coronation. The flowers are hand cut Waterford crystal, the brooch contains 66 diamonds and rose gold stamens."
see: LIVE: State Visit | The Irish Times

I paint, and all artist have a certain style. Unless the artist went in a completely different direction, the party that commissioned the portrait had some idea of what they were getting. I am not particularly fond of this portrait, it looks like a bad caricature.

Gorgeous brooch. I've loved everything she's worn today. This one looks like yellow diamonds, pink diamonds and white diamonds with a rubies (or darker pink diamonds) in the center of one of the flowers.